Question

Trebuie sa fie C. Cum rezolv?

Answer 1

3 CH3-CH2-OH + K2Cr2O7 + 4 H2SO4 = K2SO4 + Cr2(SO4)3 + 7 H2O +
3 CH3-CH=O
M etanal = 2*12+4*1+16 = 44
3*44 g etanal.........1 mol K2Cr2O7
2,2 kg etanal....................x
x =0,0166 kmoli K2Cr2O7 = 16,6 moli
randament = n practic/n teoretic * 100
n teoretic = 16,6/75*100 = 22,13 moli K2Cr2O7
cM = n/V
V = 22,13/(1/9) = 200 l

Answer 2

CH3-CH2-OH + [O] = CH3-CH=O + H2O
K2Cr2O7 + 4H2SO4 = K2SO4 + Cr2(SO4)3+ 4H2O + 3[O]
n etanol = n etanal = 2,2/44 = 0,05 kmoli = 50 moli
n etanol/nK2Cr2O7 = 3/1 ⇒ nK2Cr2O7 transformat = 50/3 moli
nK2Cr2O7 folosit = 50/3 · 100/75 = 200/9 moli
Vs = (200/9)/(1/9) = 200 l